Desktops: what works where¶

Hammunition installs radio software. Almost all of it does not care which desktop you run: a decoder, a rig control daemon or a logger is the same program under KDE Plasma, Xfce or no desktop at all. Three things do care, and this page says what is known about each of them on each desktop:

the menu that hammunition menus apply builds (Hammunition → eight groups → one submenu per category, D-050);
the tray, the switches that park and wake a GPS or a modem and start and stop services (D-056; the Controls panel);
what station costs, which matters on a low-powered machine.

The order is Parrot OS with KDE Plasma first. That is the field laptop, and it is where things are measured before anywhere else. Other desktops are welcome, and Xfce and LXQt are next, because they are what a low-powered machine usually runs. Where a row below says unmeasured, it means nobody has run it yet. It is not a promise and it is not a known failure. The checklist those runs will follow is docs/reference/vm-campaign-desktops.md.

The decision record behind this page is D-060 in docs/DECISIONS.md.

How Hammunition tells which desktops you have¶

It reads the session files your login screen lists, in /usr/share/xsessions/ and /usr/share/wayland-sessions/, and the same two directories under /usr/local/share/, which SDDM and LightDM also search. Only regular files are read (a symlink is followed to one). Each one names its desktop in a DesktopNames= line (KDE, XFCE, LXQt and so on). LXDE's and Cinnamon's session files carry no such line, so those two are recognised by file name instead: LXDE.desktop, and cinnamon.desktop, cinnamon2d.desktop or cinnamon-wayland.desktop.

Session files are on disk, so the answer is the same under sudo as outside it. The desktop you are logged into ($XDG_CURRENT_DESKTOP) is a different question, and sudo usually drops that variable. The installer never uses it. hammunition doctor shows both:

$ hammunition doctor
...
  [·] desktops       session files offer KDE Plasma, Xfce; this session is KDE Plasma
...

A container or a server has no session files at all, and doctor says exactly that. A machine whose session files name only desktops this page does not list, such as COSMIC or Sway, is a different case, and it is reported as one: doctor names the files it read (for example session files name none of the desktops the catalog knows (read: cosmic.desktop)), and a plan's reason ends (its session files name none the catalog knows: cosmic.desktop) instead of claiming there are none.

A unit for one desktop¶

A few catalog units only make sense on one desktop, and their manifest says which (the desktops field). Today there are two: hammunition-tray, the Plasma applet, and hammunition-tray-qt, for Xfce, LXQt, LXDE, MATE and Cinnamon. The applet's package depends on plasma-workspace, which is the whole Plasma shell, so installing it on an Xfce machine would drag Plasma in behind it.

So when a machine has no session for any desktop the unit is for:

In a profile (hammunition install station), the unit is deferred by name and the rest of the profile installs. The plan prints it under Will NOT happen, with the desktops it read:

Desktops read from session files (/usr/share/xsessions, /usr/share/wayland-sessions and the same under /usr/local/share):
  Xfce

Will NOT happen (the rest of the transaction still will):
  hammunition-tray: will not be installed (profile station)
      why: for KDE Plasma; this machine has no KDE Plasma session (it has: Xfce)
      → the rest installs without it; on a machine that gains a KDE Plasma session,
      `hammunition install station` again picks it up

hammunition status keeps showing the deferral until the next install. - By name (hammunition install hammunition-tray), it is refused with the same reason and what to do instead. Asking for a thing by name is asking to see why it cannot install.

If you install Plasma later, run the same hammunition install station again. It picks the applet up and leaves everything else as it is.

A machine that ran `station` before this change¶

Up to v0.10.0, station installed the Plasma applet on every machine, and the applet's package pulled in plasma-workspace. That package ships the Plasma session files. So an Xfce or LXQt machine that ran station then now has a Plasma session as far as detection can tell: it reads KDE Plasma as installed, and the applet stays planned. That answer is true of the disk, and Hammunition does not second-guess it.

If you do not want Plasma there, take the applet out and let apt remove what came in with it:

$ hammunition uninstall hammunition-tray
$ sudo apt autoremove

Read the list apt autoremove prints before you agree. It removes only packages nothing asked for by name, so a Plasma you installed on purpose stays. After that, hammunition doctor should no longer list KDE Plasma, and the next hammunition install station defers the applet.

The desktops¶

KDE Plasma (Parrot OS): first, and measured¶


Menu	Measured on the field laptop, 2026-09-12. `menus apply` writes the tree to `applications-merged/` (KDE ignores the menu prefix) and runs `kbuildsycoca6` so it shows immediately (D-050).
Tray	`hammunition-tray`, a Plasma applet. On the field laptop it was installed from its repository's own `install.sh` into `~/.local` and drew a switch for the GPS receiver (`docs/reference/bench-verification-5430.md`). Since v0.5.0 `station` installs the applet and the helper from the release's source archive (its `.deb` assets were not published); that install as root, and whether Plasma lists an applet placed without a `.deb`, are unmeasured. The Controls panel (services, radios) has not been run on this panel either. `station` plans it on a machine that has a Plasma session.
Lightweight notes	Plasma is the heaviest desktop on this page, and the one everything is tested on first.

Xfce (Xubuntu, Kali, Parrot's alternative)¶


Menu	The menu-spec path, into `xfce-applications-merged/`. Measured on the Kali VM for the earlier one-level tree (2026-09-02). The grouped tree is the same mechanism and has not been re-run there.
Tray	`hammunition-tray-qt` (v0.5.0), installed by `station` in place of the deferred Plasma applet. An earlier release was installed in a Parrot container by its release workflow; v0.5.0 through the engine, and the panel itself, are not yet run.
Lightweight notes	On a fresh machine `station` no longer pulls in Plasma here (D-060). A machine that ran `station` at v0.10.0 or earlier already has it; see above. Idle memory before and after `station` is unmeasured, and is on the Xubuntu 26.04 checklist.

LXQt (Lubuntu)¶

Lubuntu has been LXQt, not LXDE, since 18.10, so testing Lubuntu tests LXQt.


Menu	Unmeasured. Debian 13's `lxqt-menu-data` ships `/etc/xdg/menus/lxqt-applications.menu` with `<DefaultMergeDirs/>`, so the file `menus apply` writes to `lxqt-applications-merged/` is one the spec says it reads. Whether LXQt's panel menu shows it is what the Lubuntu 26.04 run will find out.
Tray	`hammunition-tray-qt` (v0.5.0), installed by `station` in place of the deferred Plasma applet. Not yet run on this panel.
Lightweight notes	Qt is already installed, so a Qt tray adds little. Idle memory is unmeasured, and is on the Lubuntu 26.04 checklist.

LXDE¶

Plain LXDE is still in Debian (openbox-lxde-session). No current Ubuntu flavour ships it.


Menu	Unmeasured. `lxmenu-data` ships `/etc/xdg/menus/lxde-applications.menu` with `<DefaultMergeDirs/>`.
Tray	`hammunition-tray-qt` (v0.5.0). lxpanel's tray is the older XEmbed kind, which Qt falls back to. Not yet run.
Lightweight notes	The lightest desktop on this page. Unmeasured here.

GNOME (Debian 13, Ubuntu)¶


Menu	GNOME cannot nest menus. The equivalent is one app folder per visible group. The code and tests exist, and the Debian 13 VM run has not happened yet (D-050).
Tray	None from Hammunition. Debian's GNOME has no system tray without an extension. Ubuntu enables its AppIndicator extension by default, so a Qt tray icon may well show there, but nobody has run one. `hammunition-tray-qt` does not list GNOME until that is measured.
Lightweight notes	Not a lightweight desktop.

MATE¶


Menu	Unmeasured. `mate-menus` ships `/etc/xdg/menus/mate-applications.menu` with `<DefaultMergeDirs/>`, and Parrot's `/etc/xdg/menus` carries a `mate-` root.
Tray	`hammunition-tray-qt` (v0.5.0) lists MATE. Not yet run.
Lightweight notes	Unmeasured.

Cinnamon (Linux Mint)¶


Menu	Unmeasured. `cinnamon-common` ships `/etc/xdg/menus/cinnamon-applications.menu` with `<DefaultMergeDirs/>`.
Tray	`hammunition-tray-qt` (v0.5.0) lists Cinnamon. Not yet run.
Lightweight notes	Unmeasured.

COSMIC (Pop!_OS)¶


Menu	Unmeasured. COSMIC's app library does not use the menu spec, and nobody has read how it groups apps (D-036, D-050).
Detection	COSMIC is not one of the desktops a manifest can name. Its session file is reported as read but unrecognised, so `doctor` names the file instead of calling the machine a server. What the file is called and what it says on Pop!_OS has not been read.
Tray	None.
Lightweight notes	Unmeasured.

The menu roots quoted above for LXQt, LXDE, MATE and Cinnamon were read from the Debian 13 packages (apt-get download, then dpkg-deb -c and -x) on 2026-09-28. That tells you which file the spec says a desktop reads, and nothing about what its panel draws.

Choosing a desktop for a low-powered machine¶

Pick whichever one you are comfortable with. Nothing in the radio software depends on the choice. If the machine is short of memory, LXQt and Xfce are the two this project will measure first. Until those runs happen, this page cannot give you numbers, and it will not guess.